SMD LED 15-11/BHC-ZL2N1QY/2T Datasheet - Blue - 1.6x0.8x0.6mm - 3.2V - 40mW - English Technical Document

1. Product Overview

The 15-11/BHC-ZL2N1QY/2T is a compact, surface-mount blue LED designed for modern electronic applications requiring high-density component placement. This device utilizes InGaN (Indium Gallium Nitride) semiconductor technology to produce blue light with a typical dominant wavelength of 468 nm. Its miniature footprint and low-profile design make it an ideal choice for space-constrained applications.

1.1 Core Features and Advantages

The primary advantages of this LED stem from its SMD (Surface Mount Device) packaging. It is supplied on 8mm tape wound on a 7-inch diameter reel, ensuring compatibility with high-speed automated pick-and-place assembly equipment. This significantly reduces manufacturing time and cost compared to through-hole components. The device is qualified for standard infrared and vapor phase reflow soldering processes, aligning with mainstream PCB assembly techniques.

Key product features include compliance with major environmental and safety standards: it is Pb-free (lead-free), incorporates ESD (Electrostatic Discharge) protection, adheres to the EU REACH regulation, and meets halogen-free requirements (Br <900 ppm, Cl <900 ppm, Br+Cl < 1500 ppm). The product is also designed to remain within RoHS (Restriction of Hazardous Substances) compliant specifications.

The small size (approximately 1.6mm x 0.8mm x 0.6mm) enables significant board space savings, higher packing density, and reduced end-product dimensions. Its lightweight construction further supports its use in miniature and portable applications.

1.2 Target Applications

This blue LED is suitable for a variety of indicator and backlighting functions. Common application areas include backlighting for automotive dashboards and switches, status indicators and keypad backlighting in telecommunication devices such as telephones and fax machines, flat backlighting for LCD panels, switch illumination, and general-purpose indicator use where a clear, bright blue signal is required.

2. Technical Specifications and Objective Interpretation

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. They are not intended for normal operation.

• Reverse Voltage (V_R): 5V. Exceeding this voltage in reverse bias can cause junction breakdown.
• Continuous Forward Current (I_F): 10 mA. The maximum DC current for reliable long-term operation.
• Peak Forward Current (I_FP): 100 mA (at 1/10 duty cycle, 1 kHz). This allows for brief pulses of higher current, useful for multiplexing or pulsed signaling, but average power must be managed.
• Power Dissipation (P_d): 40 mW. The maximum allowable power loss (V_F * I_F) at 25°C ambient temperature. Derating is necessary at higher temperatures.
• ESD Withstand (HBM): 2000V. Provides a degree of protection against electrostatic discharge during handling, but proper ESD protocols are still recommended.
• Operating Temperature (T_opr): -40°C to +85°C. The ambient temperature range for functional operation.
• Storage Temperature (T_stg): -40°C to +90°C.
• Soldering Temperature: Reflow profile peak at 260°C for max 10 seconds; Hand soldering at 350°C for max 3 seconds per terminal.

2.2 Electro-Optical Characteristics (Ta=25°C, I_F=5mA)

These parameters define the typical performance of the LED under standard test conditions.

• Luminous Intensity (I_v): 14.5 to 36.0 mcd (millicandela). The actual output is binned (see Section 3).
• Viewing Angle (2θ_1/2): 130 degrees (typical). This wide viewing angle is characteristic of the LED's lens design, providing a broad emission pattern.
• Peak Wavelength (λ_p): 468 nm (typical). The wavelength at which the spectral power distribution is maximum.
• Dominant Wavelength (λ_d): 465 to 475 nm. This defines the perceived color of the light and is also binned.
• Spectral Bandwidth (Δλ): 25 nm (typical). The width of the emitted spectrum at half the maximum intensity (FWHM).
• Forward Voltage (V_F): 2.70 to 3.20 V. The voltage drop across the LED at the test current. This parameter is binned and has a tolerance of ±0.05V within a bin.

3. Binning System Explanation

To ensure consistency in mass production, LEDs are sorted into performance bins. The 15-11/BHC-ZL2N1QY/2T uses a three-dimensional binning system for luminous intensity, dominant wavelength, and forward voltage.

3.1 Luminous Intensity Binning

Bins are defined by codes L2, M1, M2, and N1, with minimum intensities ranging from 14.5 mcd to 28.5 mcd. The bin code in the part number (e.g., 'N1' in ZL2N1QY) specifies the guaranteed minimum and maximum luminous output. A tolerance of ±11% applies to the luminous intensity.

3.2 Dominant Wavelength (Color) Binning

Wavelength is binned into two codes: 'X' (465-470 nm) and 'Y' (470-475 nm). The part number indicates this bin (e.g., ZL2N1QY). A tolerance of ±1nm is specified for the dominant wavelength.

3.3 Forward Voltage Binning

Forward voltage is sorted into five bins coded 29 through 33, corresponding to voltage ranges from 2.70-2.80V up to 3.10-3.20V. The part number indicates this bin (e.g., ZL2N1QY). The tolerance within a bin is ±0.05V.

4. Performance Curve Analysis

While specific graphical curves are not detailed in the provided text, typical electro-optical characteristics for such an LED would include:

• I-V (Current-Voltage) Curve: Shows the exponential relationship between forward current and forward voltage. The knee voltage is typically around 2.7-3.2V for blue InGaN LEDs.
• Luminous Intensity vs. Forward Current: Intensity generally increases linearly with current in the normal operating range (up to I_F), but efficiency may drop at very high currents due to heating.
• Luminous Intensity vs. Ambient Temperature: Light output typically decreases as junction temperature increases. Understanding this derating is crucial for designs operating at high ambient temperatures.
• Spectral Distribution: A plot showing the relative power emitted across wavelengths, centered around 468 nm with a ~25 nm FWHM.

5. Mechanical and Package Information

5.1 Package Dimensions

The LED has a nominal body size of 1.6mm in length, 0.8mm in width, and 0.6mm in height. The package drawing specifies the exact dimensions and tolerances (±0.1mm unless otherwise noted) for the LED body, solder pads, and the location of the cathode marking. The cathode is identified by a specific mark on the package, which is critical for correct PCB orientation.

5.2 Recommended PCB Footprint

A land pattern design that accommodates the package dimensions and allows for proper solder fillet formation should be used. The datasheet's dimensional drawing provides the basis for creating this footprint in PCB CAD software.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

For Pb-free assembly, a recommended reflow profile is provided: pre-heating between 150-200°C for 60-120 seconds, time above liquidus (217°C) for 60-150 seconds, with a peak temperature not exceeding 260°C for a maximum of 10 seconds. The maximum ramp-up rate is 6°C/sec, and the maximum ramp-down rate is 3°C/sec. Reflow soldering should not be performed more than two times.

6.2 Hand Soldering

If hand soldering is necessary, the soldering iron tip temperature must be below 350°C, and contact time per terminal must not exceed 3 seconds. A low-power iron (<25W) is recommended. A cooling interval of at least 2 seconds should be allowed between soldering each terminal to prevent thermal stress.

6.3 Storage and Moisture Sensitivity

The product is packaged in a moisture-resistant bag with desiccant. The bag should not be opened until the components are ready for use. After opening, LEDs should be stored at ≤ 30°C and ≤ 60% RH. The "floor life" under these conditions is 1 year. If the storage time is exceeded or the desiccant indicates moisture absorption, a baking treatment at 60 ± 5°C for 24 hours is required before soldering.

7. Packaging and Ordering Information

7.1 Tape and Reel Specifications

The LEDs are supplied in embossed carrier tape with dimensions specified in the datasheet. Each reel contains 2000 pieces. Reel dimensions are also provided for automated handling equipment.

7.2 Label Information

The reel label contains critical information: Customer's Product Number (CPN), Manufacturer's Part Number (P/N), Packing Quantity (QTY), and the specific bin codes for Luminous Intensity Rank (CAT), Chromaticity/Dominant Wavelength Rank (HUE), and Forward Voltage Rank (REF), along with the Lot Number.

8. Application Design Considerations

8.1 Current Limiting

Critical: An external current-limiting resistor or constant-current driver must be used in series with the LED. The forward voltage has a negative temperature coefficient, meaning it decreases as the junction heats up. Without current limiting, this can lead to thermal runaway and rapid failure (burn-out). The resistor value is calculated using R = (V_supply - V_F) / I_F.

8.2 Thermal Management

Although power dissipation is low (40mW max), proper PCB layout can help manage junction temperature. Ensure adequate copper area connected to the LED's thermal pads (if any) or the anode/cathode traces to act as a heat sink, especially when operating at high ambient temperatures or near the maximum current.

8.3 ESD and Handling

Despite built-in ESD protection, standard ESD precautions (wrist straps, grounded workstations, conductive foam) should be observed during handling and assembly to prevent latent damage.

9. Technical Comparison and Differentiation

The 15-11 package offers a balance between miniaturization and ease of handling/manufacturing. Compared to larger SMD LEDs (e.g., 3528, 5050), it saves significant board space. Compared to even smaller chip-scale packages (CSP), it is generally easier to assemble, inspect, and rework using standard SMT processes. Its wide 130-degree viewing angle differentiates it from LEDs with narrower beam angles designed for focused illumination.

10. Frequently Asked Questions (FAQ)

Q: Can I drive this LED without a series resistor if my power supply is 3.0V?

A: No. Even if the supply voltage is close to the typical V_F, the variation in V_F (bin-to-bin and with temperature) and the supply voltage tolerance make direct connection risky. A current-limiting mechanism is always required.

Q: What is the difference between peak wavelength and dominant wavelength?

A: Peak wavelength (λ_p) is the physical wavelength of maximum spectral emission. Dominant wavelength (λ_d) is the wavelength of monochromatic light that would match the perceived color of the LED. For blue LEDs, they are often very close.

Q: How do I interpret the part number '15-11/BHC-ZL2N1QY/2T'?

A: '15-11' is the package code. 'BHC' likely indicates the color (Blue) and other attributes. 'ZL2N1QY' contains the bin codes: Luminous Intensity (N1), Dominant Wavelength (Q), and Forward Voltage (Y). '2T' may refer to tape packaging.

11. Design-in Use Case Example

Scenario: Backlighting a membrane switch panel. Multiple 15-11 blue LEDs are placed behind translucent icons on a panel. A simple design would use a 5V supply. For an I_F of 5mA and a typical V_F of 3.0V, the series resistor value is R = (5V - 3.0V) / 0.005A = 400Ω. A standard 390Ω or 430Ω resistor would be suitable. The LEDs can be connected in parallel, each with its own resistor, to ensure uniform brightness despite V_F variations. The wide viewing angle ensures even illumination of the icon area.

12. Operating Principle

This LED is based on a semiconductor p-n junction made from InGaN materials. When a forward voltage exceeding the junction's built-in potential is applied, electrons and holes are injected into the active region where they recombine. In InGaN, this recombination releases energy primarily in the form of photons (light) in the blue region of the visible spectrum. The specific wavelength is determined by the bandgap energy of the InGaN alloy composition.

13. Technology Trends

The development of efficient blue LEDs, enabled by InGaN technology, was a foundational achievement in solid-state lighting, leading to the creation of white LEDs (via phosphor conversion) and the Nobel Prize in Physics in 2014. Current trends in SMD LEDs continue towards higher efficiency (more lumens per watt), increased power density in smaller packages, improved color rendering, and tighter binning tolerances for consistent performance in demanding applications like display backlighting and automotive lighting.